Leona Marie Tollett Johnson's remains were identified by the Hidalgo County Sheriff's Office on July 26, 2017, in a septic tank.

Skeletal remains discovered in the septic tank of a Texas home have been identified as a 21-year-old woman who went missing in 2004.

DNA comparison revealed the remains are those of Leona Marie Tollett Johnson, who was first reported missing more than 10 years ago, according to a press release from the Hidalgo County Sheriff’s Office.

Officials tested samples from Johnson’s 16-year-old son, who was only 3 years old when she disappeared, to confirm her identity.

“When we first approached him, he believed right away that was going to be his mother,” Sheriff Eddie Guerra told KRGV.

Authorities first uncovered the remains in July after the owner of a home in rural Edcouch discovered a large bone and boot inside their septic tank while it was being serviced.

Police have since issued an arrest warrant for 40-year-old Aristeo Cervantes Jr, who previously lived in the home off Mile 4 W Road. He’s currently serving a 12-year sentence at a Texas prison for murdering his wife in the same residence back in 2015, according to the release.

Amid questioning from investigators, Cervantes admitted to stabbing a woman 10 to 12 years ago and then placing her body in a tank, though he did not remember her name.

An autopsy performed on the remains indicated Johnson’s cause of death was homicide by stabbing, which is consistent with the suspect's confession.

Cervantes reportedly lured his victim into his car with drugs and then drove her to the home. Guerra noted Johnson had a substance abuse problem at the time of her disappearance.